Stocker air control



O. o. NYGAARD sToKER AIR CONTROL Filed March 25, 1923 Aug. 3l 1926.

2 Sheets-Sheet l H .Ilm L mmm/Ey Aug, B N261 Q. O NYGAARD smoxm AIR CONTROL Filed March 23, 1923 2 Sheets-Sheet 2 .WQ o o on NN @o oo o 35 SOOQQ @oo 20023 Q 230000 2Q @@0020 QQ@ ESOS@ GOO QCQOOQQ A 7' TOR/VE Y Patented Augfsi, 192e.

, iseaooi osoAn o. Nxt-mann, or savons, massac Husnrrs, Assicaron 'ro coMBUs'rIoN ENGI- NEERING CORPORATION, F YORK, N. Y., OF NEW-YORK.

' sro'xna un common. l

application niednarch as, 1923. serial No. samen My present invention relatesl to strokers,

Vand more particularly to-Van improved method of and apparatus lfor distributing' and regulating the iow of air to the fuel 6 bed in automatic stokers.

In stocking apparatus, and particularly in automatic stoking apparatus of the types 1n use-at the present day, and with the type of 4fuel necessarily employed therewith, it becomes essential for a proper economical working of the apparatus to provide oxy,

gen containing fluid, lsuch as air, to the 'fuel bedin proportion to the depth of ,fuel in the bed at any point throughout the lengthV should the fuel bed burn through at Aany thereof, and in the past, 1^ although many. attempts have been madezto devise means for regulating the amount of air to the fuel bed, all su'c'h devices have failed to function properly as they operated over too great an area of the stoker. A great many automatic st'okers are made extremelyl large and the tendency is for such units to become largerand larger as time goes on with the result n that the difference in the depth or thickness of the fuel bed on the'y grate at the receiving or inlet end and alt the dumping or exit end thereof is continually increasing.-y

An average depth of fuel bedparticularly in underfeed .stokers is at present from thirty to thirty six inches at the receiving end and from six to eight inchesat the dumping end of the grate. Itis evident that a fuel bed thus proportioned should not be supplied with an equal quantity of air-V at all points therein, nor with air of the same pressure and velocity as such air would f .bypass the thick portion of the fuel bed and Eun holes in the thin portion of the fuel Previous practice has been to use an amount of air and of apressure suitable to a point in ythe 'fuel bed about half way between the thickest and the thinnest portions of the same and dependin on a very high distance between the surface of the fuel bed and the lower rows of tubes or heating surface of the boiler for a complete `mixture and combustion of the gases generated.

This practice has necessitateda great outlay of money for very high boiler settings and the necessary building or housing sur'- rounding .such setting.. It will be possible by the use of my method of distributing and regulating the air to the fuel bed in quantities, pressures and velocities in accordance travel with the thickness of the fuel bed, to make such, excessively high and expensive boiler settings unnecessary, in that I amenabled to supply the right amount of air to every point in he fuel bed, thus' formingthe right mixture of gases in thefuel bed which, assures complete combustion of the fuel in at, or near thesurface thereof, instead of depending as in previous rpractice on a lon l of the gases .to assure mixing an completel combustionv before they'4 become chilled through contact with the 'heating surfaceof the boiler. y y Another feature of my invention is that,

particular point, or the tuyresfail to oper-` ate at any particular point, or the fuel feeding means for any particular fueljtrough Y fail tooperate, whereby fuel4 in "such trough wouldv very quickly burn out and allow excess airto enter the furnace, I have provided novelmeans whereby` the` air to such burned out portions can be regulated or completely shut off at -will` and local faults quickly remedied. 4

An underfeed stoker is usually made up of severeal units or ,fuel troilghs spaced in p position sideby side and several units may be operated from a common driving means. W'hen. the driving means fails to operate or any one of the units fails to function,

or several units is so. severe that it has'been found necessary to'shut down and discontinue the operation of the wholefurnace andv boiler. n

In my method of distributing air to the fuelbed IA regulate the air flow to each row of tuyres or units independently from' lany other unit; thus, should any unit or any part of the uniit become disabled I have4 ready means to regulate or shut oif .such unit from the air supply and thereby maintain the rest of the furnace in economical operation. y None of the' devices in use at 100 the present time provide means for over' coming the diiiiculty of local faults and while they have been successful in admitting the air to the fuel bed, considering the fuel bed asl a init, they have not been suc- 105 cessful in curing local faults or of bein-g able to shut down 'or shut olf the supply of air to a disabled fuel trough while permit#` ting the ,feeding `of air to the remaining gpod fuel troughs. So far as I am aware, 110

.sol

there have been no means devised I whereby the 'air ,'supplied'tothe fuel bed at any point along the fuel troughs.

In my present' invention I have obviated the l'objectionable features above noted and have designed an air feedingmeans in.

-, which the air to each fuel troughis supplied from a common pressure or wind chamber'V and in which the air supplied toeach trough 'separately may be regulated as Aregards amount and velocity according to thedepth -of fuel at any point along the length of the trough and means are associated with such 'mechanisms for varying the'amount of lair supplied. I have 'arranged the air control- 4 1mg means for each trough independent of every' other 'unit in the stoker and may control the admission of air to thetrough from no air at all'to full flow of air and 'am thus Aenabledto completely shut off the sup` ply of air tofany trough or' rowof tuyeres should the fuel supply means for such trough fail to function ory should a. localized invention associated therewith;

burning out occur, I may shut oli' the supply of air to this particular trough,'thus puttlng the same out of -commission while yet retain# ingthe fuel troughs ofthe rest of the stoker in commission; y j l My invention is applicable to any of the existing forms of automatic stokers employing the usual form of tuyres and in the showing of my invention Iliave illustrated the' applicability of the same to the various forms of tuyres and it is to be understood that my invention Ais not limited to the form of tuyre that may be employed' or to the Itype 'of stoker apparatus that may be employed, but is applicable to any form of fuel burning apparatus wherein a fuel bed is employed and to which' it is necessary to adriit air for the proper consumption of the fue 1 i i In theaccompanying drawings, V Fig; 1 is a section l side elevation through' .the center Aof a row of tuyres showing my F ig. 2 is a sectional elevation on the line of Fig. 1; and

Fig. 3 is a detail showing the. means f or regulating the throw of the air admis' S1011 means.

Referring vto the drawings, 10 'designates a foundation 'on whichJ4 is mounted the spaced fuel troughs 11 constituting supports r for the tuyere' blocks, and 12 designates a portion of the brick masonry enclosing the- Stoker apparatus, a channel iron 13 extending across the' furnace land acting as a sup port for fthe frontend of the fuel troug s 11, a plate 14 enclosing the space extending.

resting on,

ldefined by ner and by means of which fthe supply o f- Referring now particularly to Figs. 1 and 2, it is assumed that the-'form'of tuyre block designated by 15` has been employed, which tuyre block. consists essentially of a substantially wind or pressure chamber is conand spanning, the space between adjacenttroughsll, 'such fuel supports being provided with a plurality of orifices 23- through which air may flow and with a floorplate 24, the distance between Hoor plates, as clearly Ishown in Fig. 1, constituting a passage extending from the air pressure chamber 19 to the orifices 23. Pivotally se` cured to the sides of stantially midway between adjacent` floor plates- 24 by bolts 25 are downwardly extending members. 2 6 .at' the upper ends of which and formed integrally therewith is a right' angledv plate. 27, the 'length and breadth of. this member 27 being substantially 'equal to the 'area sides 84 of tuyres 15. It is obvious, there fore, that, if themember pivoting bolt 25,.-the plate 27 may be swung into such a position as to completely shut oli' the flow of air to the orifices 23 ofv any tuyre block 15, and it-is understood that there is one such plate 27 for each ofthe tuyre blocks 15. The downwardly extending members 26 are each provided with a slot 2'8. bar 29 substantially equal to the length of the inclined arrangedtuyre blocks v 15 is provided at intervals with bolts 30 each of which' bolts extends through the slot 28 on the downwardly extending inembers 26, the position of the bar 29 with relation to its slot being adjustable while the bolts 30 are arranged to be rotatably mounted in the bar 29. By this means movement of the lbar 29 causes a rotative movement of the members 26 about their pivot bolts 25 and, therefore, ya correspondlng movement onthe part oftheplates 27 with respect to the tuyreblocks 15 and, therefore, such structure provided `means adjacent floor plates. 24 and the' 27 is swung on its' between the side walls and the base 10' semi-cylindrical fuel support 22 the troughs 11 and sub'- for regulating the flowA of'air from the wind or pressure chamber 19 to the orifices 23 in the tuyre blocks 15. Secured to.- the bar 29 and intermediate the ends thereof is a stud l32 which passes through and is ass'v ciated with a slot 33 'in-a lever 34 that is secured to a shaft 35 rotatably mounted in pillowl blocks 36 -secured'to the underside of the, troughs 11. Secured to the shaft at any convenient point alon the length thereof is adownwardly exten ing vlever 37 to the lower endof which'V is pivotally mounted one end of an operating'bar 38 the other, end of which extends through the Wall 14 .y

and is bent at right angles 'at 39t0 provide a convenient handhold forvan operator.'

It understood, of course', thatv there is a plate-27 Vfor each of thetuyre blocks-1.5, and, Ain addition, I Ahave arrangedone of such plates -27 for each of the overfeed.;

grates 40.v Also, the tuyre blocks 15 and vthe overfeedgrates are arranged in rows and by the construction above described :Il

am enabled, by the manipulationof the operating rod 38, to move the plates 27""of each row ofV tuyre blocks andi overfeed grates simultaneously. lIt should be understood, however, that I may provide a plurality of shortA shafts 35 and la lurality of operating levers" 38 so as to ma e it possithe orifices 23 of the .topmost tuyre block' 15 in order to provide sufficient air for the combustion of the fuel in the trough, which fuel is thickest at this point, while the plate 27 in the lowermost tuyre block 15 or in `the lowermost overfeed grate'40 will have a minimum opening, as shown in Fig. 1, as the fuel bed at this point `is thinnest and the intermediate. plates 27 will grade from the largest opening down to the smallest opening to provide air-in predetermined amounts corresponding with the thickness of the fuel bed, thisconstruction being clearly shown in Fig. 1. lt will be understood that the position and throw of the lowermost and inter- 'mediate plates 27 may be varied in respect to the uppermost plate 27 by adjusting the bolt'3() in the slots 28. -l may, in place ofthe construction above described; that is, ar-l ranging the' bar 29 with relation to the slots 28 to carry out the object above described, make the depending portions 26 gradually increasing in lengthv from the topmost one to the lowermost one when it will lbe noted that, with the bar 29 in the lowermost position of the slot .28, the same result as that described above will be attained. its another alternative to the construction above described, l may substitute for the downwardly extending member 26- with the in-v tegrally'formed plate 27 thereof, 'a right angled plate 42, the downwardly extending portion of which is pivotally mounted at 43 to the sides of the troughs 11, and with the pivot point 43 as a center vIpro-vide in arcuate slot 44.I -Pivotally mounted fon the pivot point-43and extending downwardly therefrom is a lever 45 provided at its lower end .with a longitudinally extending slot- 46 the downwardly extending portion of 42 an that engages with the stud 32 in the' bar 29, y.

and assoclated with the arcuateslot 44 and passing through a perforation inthe lever 45 is a threaded'bolt 47 'provided onvitsouter end with a wing nut 48 and by means of which the lever45 and downwardly exi tending` portion of 42may be clamped together in adjusted-position. Secured to the horizontal portion of the member `42 is a vplate 49 equal in superficial area to "the" plates 27. By this construction the necessity of adjustment of the rod 29 with respect to the levers 45 or their equivalents, thev downwardly extending members 26for degree of opening of the plates 49 or 27 with l i respect to the adjacent floor plates 24 is dispensed with, it being possible by this method to,4 individually adjust each plate 49 with respect to the adjacent ldoor plates 24 with which it is associated. j 1

Various other forms than those described will suggest themselves to those skilled in the art and it isto beunderstood that my invention consists essentiallyin regulating the flow of air to a fuel bed of an automatic stolter, the amount of air being regulated in accordance with the thickness and'requirements of the fuel bed at any particular point and may accomplish this desirable result by means that may be adjusted from time to time so as to'distribute the air over the entire fuel bed or @ver a predetermined por'- tion of any of the fuel troughs or permanently arrange the controlling means.

While l have, therefore, necessarily described the preferred embodiments of my invention somewhat lin detail, it is to beunderstood that l may vary in the size, shape,

Aand arrangement of parts within wide limits without departing from the spirit of the invention.

'Having thus described my what I claim as new is:

1. ln an automatic'stoker, a fuel trough, tuyeres in stacked relation alongthe length and at the sides of said trough, each tuyere having 'a floor plate, and adjustable means between adjacent floor plates for regulating invention,

the amount of 'air flowing through each tuyre. l

2. ln an automatic Stoker, a fuel trough,

tuyres in stacked relation along thelength and at the sides of, said trough, each tuyre having a floor plate, and means between adn each tuyre.

jacent floor plates capable of being" adj usted for regulating the? ow of air through 3..Inan automatic-stoker,a fueltrough,

5 an air channel at each side-thereof, tuyres plate vfor* detrmnmg the flou' of air through each tuyre. 10

'In testimony whereof, Ihave signed my name to this specification, at Boston, Massachusetts, this tenth day of March, A. D. 1923.

OSCAR o. NYGAARD. 

